"v. 46, p. 449-471. Volcanogenic massive sulfide ore deposit Volcanogenic massive sulfide ore deposits, also known as VMS ore deposits, are a type of metal sulfide ore deposit, mainly copper-zinc which are associated with and created by volcanic-associated hydrothermal events in submarine environments. These deposits are also sometimes called volcanic-hosted massive sulfide (VHMS) deposits. The density generally is 4500 kg/m. They are predominantly stratiform accumulations of sulfide minerals that precipitate from hydrothermal fluids on or below the seafloor in a wide range of ancient and modern geological settings. In modern oceans they are synonymous with sulfurous plumes called black smokers."
"to have occurred approximately 1 billion years ago. There are a few sulphides and oxide minerals that form within the ore that are a particular interest, the major one being sphalerite. Galena, pyrite, pyrrhotite, and marcasite commonly occur with the sphalerite along with some minor arsenopyrite and chalcopyrite. Gahnite and rutile are the most common oxide minerals that form within the ore, with rutile being the most abundant. Graphite is also a mineral that is commonly found within the ore and surrounding rock. Extracted deposits through drilling, blasting, and underground mining methods are loaded and taken to be processed while"
"Wolframite Wolframite, (Fe,Mn)WO, is an iron manganese tungstate mineral that is the intermediate between ferberite (Fe rich) and hübnerite (Mn rich). Along with scheelite, the wolframite series are the most important tungsten ore minerals. Wolframite is found in quartz veins and pegmatites associated with granitic intrusives. Associated minerals include cassiterite, scheelite, bismuth, quartz, pyrite, galena, sphalerite, and arsenopyrite. This mineral was historically found in Europe in Bohemia, Saxony, and Cornwall. China reportedly has the world's largest supply of tungsten ore with about 60%. Other producers are Canada, Portugal, Russia, Australia, Thailand, South Korea, Rwanda, Bolivia, the United States, and the"
"the matrices of galena and sphalerite, invisible to the naked eye but visible in microscope. The silver content in typical galena-dominated Sala ore was about 0.15% to 1%, the latter being one of the highest contents of silver in galena ever reported. In the sphalerite-dominated ore, the silver content is only about 0.015-0.02%, which was still enough to exploit and would even be at present days, given that a sufficient tonnage of metallurgically advantageous ore could be found. The bedrock was created about 1,89 billion years ago during the paleoproterozoic era. The host rock to the mined ore is dominated"
"tetrahedrite as ore minerals along with common accessories pyrite, pyrrhotite, quartz, carbonates and graphite. Minor arsenopyrite, marcasite, chalcopyrite, valleriite, proustite, polybasite and argentite also occur. Original surface oxidized ore contained cerussite, anglesite and pyromorphite. Silver and zinc were removed from the surface oxidized zone and were deposited as supergene ore at a depth above the primary ore. Copper occurs in brecciated ""silica-dolomite"" rock. Primary minerals are chalcopyrite, pyrrhotite and arsenopyrite. minor amounts of cobaltite, marcasite, valleriite, chalcostibite, galena and others are reported. Smelter operations release sulfur dioxide emissions very close to the city of Mount Isa. The Mount Isa Mines"
"However, due to its variable trace element content, sphalerite is also an important source of many minor metals, such as cadmium, gallium germanium, and indium. Crystals of suitable size and transparency have been fashioned into gemstones, usually featuring the brilliant cut to best display sphalerite's high dispersion of 0.156 (B-G interval), over three times that of diamond. Freshly cut gems have an adamantine luster. Owing to their softness and fragility the gems are often left unset as collector's or museum pieces (although some have been set into pendants). Gem-quality material is usually a yellowish to honey brown, red to orange,"
"The mine followed a 0.50 to 1.20 m wide lode close to the SSE-striking border fault. The vertical to steeply North dipping, mineralized lode is striking N 115 to N 120. The matrix of the lode consists of quartz and baryte, in some places only of baryte. The lode contains as ore minerals the sulfides galena, sphalerite, marcasite and pyrite as well as the lead alteration mineral cerussite. Galena and sphalerite are silver-bearing. The silver concentration in galena varies between 112 and 400 grams per ton, exceptionally reaching values as high as 1708 g/t. The silver concentration in sphalerite is"
"Galena Galena, also called lead glance, is the natural mineral form of lead(II) sulfide. It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite. Galena is the main ore of lead, used since ancient times. Because of its somewhat low melting point, it was easy to liberate by smelting. It typically forms in low-temperature sedimentary deposits. In some deposits galena contains about"
"Safflorite Safflorite is a rare cobalt iron arsenide mineral with formula: (Co,Fe)As. ""Pure"" safflorite would be just CoAs, but iron is virtually always present. Safflorite is a member of the three-way substitution series of arsenides known as the loellingite or loellingite group. More than fifty percent iron makes the mineral loellingite whereas more than fifty percent nickel and the mineral is rammelsbergite. A parallel series of antimonide minerals exist. Safflorite along with the other minerals crystallize in the orthorhombic system forming opaque gray to white massive to radiating forms, Clinosafflorite has a monoclinic symmetry. It has a mohs hardness of"
"Theralite Theralite (from Greek ""to pursue"") is, in petrology, the name given to calcic foidal gabbro, a plutonic hylocrystalline rock consisting of augite, olivine, calcic plagioclase (labradorite), and nepheline, along with accessories including biotite, magnetite, ilmenite and analcime. Theralite is the intrusive equivalent of nepheline basanite, a foidal basalt with essential calic plagioclase and essential olivine. Tephrite is foidal basalt with essential calic plagioclase but without essential olivine. It is essentially the volcanic equivalent of essexite. The discovery of theralite was looked forward to with interest as completing the series of basic rocks containing nepheline as an essential constituent. With"
"material is usually a strong yellow to honey brown, orange, red, or green; its very high RI (2.37) and dispersion (0.156) make for an extremely lustrous and fiery gem, and it is also isotropic. But here again, its low hardness (2.5–4) and perfect dodecahedral cleavage preclude sphalerite's wide use in jewelry. Two calcium-rich members of the garnet group fare much better: these are grossularite (usually brownish orange, rarely colorless, yellow, green, or pink) and andradite. The latter is the rarest and most costly of the garnets, with three of its varieties—topazolite (yellow), melanite (black), and demantoid (green)—sometimes seen in jewelry."
"Scorzalite Scorzalite ((Fe,Mg)Al(OH,PO)) is a dark blue phosphate mineral containing iron, magnesium, and aluminium phosphate. Scorzalite forms one endmember of a solid solution series with the lighter, more magnesium-rich lazulite. Scorzalite crystallizes in the monoclinic system in a dipyramidal form. It has a Mohs hardness of 5.5-6 and a specific gravity of 3.4. It is infusible and insoluble in water, and only slightly soluble in warm hydrochloric acid. It was first described in 1947 for an occurrence in the granite pegmatite in the Córrego Frio mine, Linópolis, Doce valley, Minas Gerais, Brazil. It was named for the Brazilian geologist Everisto"
"oxygen and water over time to cause swelling and cracking. Pyrrhotite Pyrrhotite is an iron sulfide mineral with the formula FeS (x = 0 to 0.2). It is a nonstoichiometric variant of FeS, the mineral known as troilite. Pyrrhotite is also called magnetic pyrite, because the color is similar to pyrite and it is weakly magnetic. The magnetism decreases as the iron content increases, and troilite is non-magnetic. Pyrrhotite exist as a number of polytypes of hexagonal or monoclinic crystal symmetry; several polytypes often occur within the same specimen. Their structure is based on the NiAs unit cell. As such,"
"Pyrite The mineral pyrite, or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula FeS (iron(II) disulfide). Pyrite is considered the most common of the sulfide minerals. Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of ""fool's gold"". The color has also led to the nicknames ""brass"", ""brazzle"", and ""Brazil"", primarily used to refer to pyrite found in coal. The name ""pyrite"" is derived from the Greek πυρίτης (""pyritēs""), ""of fire"" or ""in fire"", in turn from πύρ (""pyr""), ""fire"". In ancient Roman times,"
"Pyrrhotite Pyrrhotite is an iron sulfide mineral with the formula FeS (x = 0 to 0.2). It is a nonstoichiometric variant of FeS, the mineral known as troilite. Pyrrhotite is also called magnetic pyrite, because the color is similar to pyrite and it is weakly magnetic. The magnetism decreases as the iron content increases, and troilite is non-magnetic. Pyrrhotite exist as a number of polytypes of hexagonal or monoclinic crystal symmetry; several polytypes often occur within the same specimen. Their structure is based on the NiAs unit cell. As such, Fe occupies an octahedral site and the sulfide centers occupy"
"Khmaralite The mineral khmaralite is a beryllium bearing mineral of the sapphirine group with a chemical formula of (Mg,Al,Fe)[(Al,Si,Be)O]O. It is most associated with sillimanite, surinamite, musgravite, garnet, and biotite. The known color is a dark greenish blue or a dark green, with a colorless streak. It is transparent with a vitreous luster with no cleavage and a Moh's hardness of 7. It is brittle with an uneven fracture. The calculated density is 3.61 g/cm. Khmaralite is closely related to sapphirine with a difference in the tetrahedral sequence chain. The tetrahedral sequence chain in sapphirine (Al-Si-Al) is replaced by the"
"ore of titanium; other examples include cassiterite (SnO; ore of tin), and pyrolusite (MnO; ore of manganese). In hydroxides, the dominant anion is the hydroxyl ion, OH. Bauxites are the chief aluminium ore, and are a heterogeneous mixture of the hydroxide minerals diaspore, gibbsite, and bohmite; they form in areas with a very high rate of chemical weathering (mainly tropical conditions). Finally, multiple oxides are compounds of two metals with oxygen. A major group within this class are the spinels, with a general formula of XYO. Examples of species include spinel (MgAlO), chromite (FeCrO), and magnetite (FeO). The latter is"
"Sperrylite Sperrylite is a platinum arsenide mineral with formula PtAs and is an opaque metallic tin white mineral which crystallizes in the isometric system with the pyrite group structure. It forms cubic, octahedral or pyritohedral crystals in addition to massive and reniform habits. It has a Mohs hardness of 6 - 7 and a very high specific gravity of 10.6. It was discovered by Francis Louis Sperry, an American chemist, in 1889 at Sudbury. The most important occurrence of sperrylite is in the nickel ore deposit of Sudbury Basin in Ontario, Canada. It also occurs in the layered igneous complex"
"Smaltite Smaltite is a variety of the mineral skutterudite consisting of cobalt iron nickel arsenide: (Co,Fe,Ni)As. Smaltite crystallizes in the cubic system with the same hemihedral symmetry as pyrite; crystals have usually the form of cubes or cubo-octahedra, but are imperfectly developed and of somewhat rare occurrence. More often the mineral is found as compact or granular masses. The color is tin-white to steel-grey, with a metallic luster; the streak is greyish black. Hardness is 5.5 and the specific gravity is 6.5. The cobalt is partly replaced by iron and nickel, and as the latter increases in amount there is"
"conditions under which the sphalerite formed, most importantly formation temperature and fluid composition. Its color is usually yellow, brown, or gray to gray-black, and it may be shiny or dull. Its luster is adamantine, resinous to submetallic for high iron varieties. It has a yellow or light brown streak, a Mohs hardness of 3.5–4, and a specific gravity of 3.9–4.1. Some specimens have a red iridescence within the gray-black crystals; these are called ""ruby sphalerite"". The pale yellow and red varieties have very little iron and are translucent. The darker, more opaque varieties contain more iron. Some specimens are also"
"iron pyrite, a common mineral, is usually described as consisting of Fe and the persulfido anion S. The sulfur atoms within the disulfido dianion are bound together via a short S-S bond. ""Late"" transition metal disulfides (Mn, Fe, Co, Ni) almost always adopt the pyrite or the related marcasite motif, in contrast to early metals (V, Ti, Mo, W) which adopt 4+ oxidation state with two chalcogenide dianions. Several metals, mainly for the early metals (Ti, V, Cr, Mn groups) also form trichalcogenides. These materials are usually described as M(E)(E) (where E = S, Se, Te). A well known example"
"ores are known. The only cadmium mineral of importance, greenockite (CdS), is nearly always associated with sphalerite (ZnS). This association is caused by geochemical similarity between zinc and cadmium, with no geological process likely to separate them. Thus, cadmium is produced mainly as a byproduct of mining, smelting, and refining sulfidic ores of zinc, and, to a lesser degree, lead and copper. Small amounts of cadmium, about 10% of consumption, are produced from secondary sources, mainly from dust generated by recycling iron and steel scrap. Production in the United States began in 1907, but wide use began after World War"
"sulfide consists of over 90% iron sulfide, mainly in the form of pyrite, with chalcopyrite, sphalerite and galena also being major constituents. Magnetite is present in minor amounts; as magnetite content increases, the ores grade into massive oxide deposits. The gangue (the uneconomic waste material) is mainly quartz and pyrite or pyrrhotite. Due to the high density of the deposits some have marked gravity anomalies (Neves-Corvo, Portugal) which is of use in exploration. Alteration haloes developed by VMS deposits are typically conical in shape, occur mostly stratigraphically below the original fluid flow location (not necessarily the ore itself), and are"
"Scheelite Scheelite is a calcium tungstate mineral with the chemical formula CaWO. It is an important ore of tungsten (wolfram). Well-formed crystals are sought by collectors and are occasionally fashioned into gemstones when suitably free of flaws. Scheelite has been synthesized using the Czochralski process; the material produced may be used to imitate diamond, as a scintillator, or as a solid-state lasing medium. It was also used in radium paint in the same fashion as was zinc sulphide, and Thomas Edison invented a fluoroscope with a calcium tungstate-coated screen, making the images six times brighter than those with barium platinocyanide;"
"Melanterite Melanterite is a mineral form of hydrous iron(II) sulfate: FeSO·7HO. It is the iron analogue of the copper sulfate chalcanthite. It alters to siderotil by loss of water. It is a secondary sulfate mineral which forms from the oxidation of primary sulfide minerals such as pyrite and marcasite in the near-surface environment. It often occurs as a ""post mine"" encrustation on old underground mine surfaces. It also occurs in coal and lignite seams exposed to humid air and as a rare sublimate phase around volcanic fumaroles. Associated minerals include pisanite, chalcanthite, epsomite, pickeringite, halotrichite and other sulfate minerals. It"
"Siderite Siderite is a mineral composed of iron(II) carbonate (FeCO). It takes its name from the Greek word σίδηρος ""sideros,"" “iron”. It is a valuable iron mineral, since it is 48% iron and contains no sulfur or phosphorus. Zinc, magnesium and manganese commonly substitute for the iron resulting in the siderite-smithsonite, siderite-magnesite and siderite-rhodochrosite solid solution series. Siderite has Mohs hardness of 3.75-4.25, a specific gravity of 3.96, a white streak and a vitreous lustre or pearly luster. It crystallizes in the trigonal crystal system, and are rhombohedral in shape, typically with curved and striated faces. It also occurs in"
"Wurtzite Wurtzite is a zinc iron sulfide mineral ((Zn,Fe)S) a less frequently encountered mineral form of sphalerite. The iron content is variable up to eight percent. It is trimorphous with matraite and sphalerite. It occurs in hydrothermal deposits associated with sphalerite, pyrite, chalcopyrite, barite and marcasite. It also occurs in low-temperature clay-ironstone concretions. It was first described in 1861 for an occurrence in the San José Mine, Oruro City, Cercado Province, Oruro Department, Bolivia, and named for French chemist Charles-Adolphe Wurtz. It has widespread distribution. In Europe it is reported from Příbram, Czech Republic; Hesse, Germany; and Liskeard, Cornwall, England."
"reaction with the liner, and no longer required spiegeleisen. From the 1880s demand for the ores fell once again and many of their mines, including those of the Brendon Hills, closed soon after. Siderite Siderite is a mineral composed of iron(II) carbonate (FeCO). It takes its name from the Greek word σίδηρος ""sideros,"" “iron”. It is a valuable iron mineral, since it is 48% iron and contains no sulfur or phosphorus. Zinc, magnesium and manganese commonly substitute for the iron resulting in the siderite-smithsonite, siderite-magnesite and siderite-rhodochrosite solid solution series. Siderite has Mohs hardness of 3.75-4.25, a specific gravity of"
"are pseudofossils and lack the pentagonal symmetry of the animal. Pyrite The mineral pyrite, or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula FeS (iron(II) disulfide). Pyrite is considered the most common of the sulfide minerals. Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of ""fool's gold"". The color has also led to the nicknames ""brass"", ""brazzle"", and ""Brazil"", primarily used to refer to pyrite found in coal. The name ""pyrite"" is derived from the Greek πυρίτης (""pyritēs""), ""of fire"" or ""in fire"","
"than 10 indium minerals such as roquesite (CuInS) are known, and none occur at sufficient concentrations for economic extraction. Instead, indium is usually a trace constituent of more common ore minerals, such as sphalerite and chalcopyrite. From these, it can be extracted as a by-product during smelting. While the enrichment of indium in these deposits is high relative to its crustal abundance, it is insufficient, at current prices, to support extraction of indium as the main product. Different estimates exist of the amounts of indium contained within the ores of other metals. However, these amounts are not extractable without mining"
"in ores. Zinc is a chalcophile, meaning the element is more likely to be found in minerals together with sulfur and other heavy chalcogens, rather than with the light chalcogen oxygen or with non-chalcogen electronegative elements such as the halogens. Sulfides formed as the crust solidified under the reducing conditions of the early Earth's atmosphere. Sphalerite, which is a form of zinc sulfide, is the most heavily mined zinc-containing ore because its concentrate contains 60–62% zinc. Other source minerals for zinc include smithsonite (zinc carbonate), hemimorphite (zinc silicate), wurtzite (another zinc sulfide), and sometimes hydrozincite (basic zinc carbonate). With the"
"Pyroxferroite Pyroxferroite (Fe,Ca)SiO is a single chain inosilicate. It is mostly composed of iron, silicon and oxygen, with smaller fractions of calcium and several other metals. Together with armalcolite and tranquillityite, it is one of the three minerals which were discovered on the Moon. It was then found in Lunar and Martian meteorites as well as a mineral in the Earth's crust. Pyroxferroite can also be produced by annealing synthetic clinopyroxene at high pressures and temperatures. The mineral is metastable and gradually decomposes at ambient conditions, but this process can take billions of years. Pyroxferroite is named from ""pyroxene"" and"
"economically significant PGE deposits include mafic intrusions related to flood basalts, and ultramafic complexes of the Alaska, Urals type. Typical ores for PGMs contain ca. 10 g PGM/ton ore, thus the identity of the particular mineral is unknown. Platinum can occur as a native metal, but it can also occur in various different minerals and alloys. That said, Sperrylite (platinum arsenide, PtAs) ore is by far the most significant source of this metal. A naturally occurring platinum-iridium alloy, platiniridium, is found in the mineral cooperite (platinum sulfide, PtS). Platinum in a native state, often accompanied by small amounts of other"